Adaptive Maps Query
Discussion
Assuming you don't have excessive play in your shafts, your pots & Lambdas are good & that you have got the 4.5 throttle bodies I'd guess it's normal for them to be different, more so in a 4.5 than a 4.2.
(Arcing plug leads can be an issue too, worth looking a the coil packs end of the leads in the dark with the engine running.)
The butterflies open the wrong way for a V engine, they should be a mirror image of each other, you get differing air flow & swirl into the engine at lower openings, Dave Walker pointed that out to me years ago. The 4.2 has the butterflies much further back up the inlets so it a lot less of a problem for them. Dave said no other flat plain crack V8 uses twin adaptives, you don't need them if both sides of the engine are working in sync.
I used a Jenvey linkage on our 4.5 & made mine open in a mirror image, I've finally got the mapping correct & the pickup is mental now, insanely instant response - as any big NA V8 in throttle bodies should be, it was always more like a turbo car before.
Maybe other people found pick up was better after a Joolz remap but mine was just as bad as it had ever been after a remap by Emerald, John there commented how bad the pick up was (plug leads could have been a factor though) .
I just got my other Cerb that's actually a 4.5 but sold as a 4.2 with 4.2 inlets running & the stock pick up on that is better than the stock 4.5 pickup.
The pick had never been good for all the 23 years we've had the 4.5, it's like a new car now!
(Arcing plug leads can be an issue too, worth looking a the coil packs end of the leads in the dark with the engine running.)
The butterflies open the wrong way for a V engine, they should be a mirror image of each other, you get differing air flow & swirl into the engine at lower openings, Dave Walker pointed that out to me years ago. The 4.2 has the butterflies much further back up the inlets so it a lot less of a problem for them. Dave said no other flat plain crack V8 uses twin adaptives, you don't need them if both sides of the engine are working in sync.
I used a Jenvey linkage on our 4.5 & made mine open in a mirror image, I've finally got the mapping correct & the pickup is mental now, insanely instant response - as any big NA V8 in throttle bodies should be, it was always more like a turbo car before.
Maybe other people found pick up was better after a Joolz remap but mine was just as bad as it had ever been after a remap by Emerald, John there commented how bad the pick up was (plug leads could have been a factor though) .
I just got my other Cerb that's actually a 4.5 but sold as a 4.2 with 4.2 inlets running & the stock pick up on that is better than the stock 4.5 pickup.
The pick had never been good for all the 23 years we've had the 4.5, it's like a new car now!
I don't think you can look at the adaptive maps and definitely say there is any kind of problem. A lot will be down to driving style. What gear are you predominantly in at TPS 2 between 3,000rpm & 4,000rpm. Are you motorway cruising in 5th or urban driving in 2nd / 3rd. For the same TPS and engine speed they will have different maps.
I would say it looks quite healthy with both banks responding in very similar manner. If anything perhaps running slightly rich - with the odd bank just slightly richer than the even. You can confirm this by looking at a recorded graph
e.g.
Mine is running slightly lean . .
The graph for this show the real time adaptive values mainly ranging between 0 and 20, and the lamda's spend slightly more time on 0 than 1 (0 = lean, 1 = rich).
To me this is a bit more meaningful, but also does backup my thinking that the stored adaptive map looks slightly lean. I'll be giving it another 0.2 or 0.4 of a degree on the throttle pots at the next tune up.
At the end of the day the adaptive maps will be constantly changing and you just have to ask yourself "Is the car driving ok?"
If so - don't obsess over the maps too much. At least both your banks are storing values. For the past 20 years mine has stubbornly refused to record much of anything in the odd bank. I've even sent the ECU to powers for testing. Couldn't find a fault. And so my engine runs best off the base map when I've zero'd out the even values. Ho hum.
I would say it looks quite healthy with both banks responding in very similar manner. If anything perhaps running slightly rich - with the odd bank just slightly richer than the even. You can confirm this by looking at a recorded graph
e.g.
Mine is running slightly lean . .
The graph for this show the real time adaptive values mainly ranging between 0 and 20, and the lamda's spend slightly more time on 0 than 1 (0 = lean, 1 = rich).
To me this is a bit more meaningful, but also does backup my thinking that the stored adaptive map looks slightly lean. I'll be giving it another 0.2 or 0.4 of a degree on the throttle pots at the next tune up.
At the end of the day the adaptive maps will be constantly changing and you just have to ask yourself "Is the car driving ok?"
If so - don't obsess over the maps too much. At least both your banks are storing values. For the past 20 years mine has stubbornly refused to record much of anything in the odd bank. I've even sent the ECU to powers for testing. Couldn't find a fault. And so my engine runs best off the base map when I've zero'd out the even values. Ho hum.
notaping said:
At the end of the day the adaptive maps will be constantly changing and you just have to ask yourself "Is the car driving ok?"
That is very true! However I just thought, you mentioned you had been driving with a duff temp sensor for a long time? If that was recently it will have messed up you adaptives a lot.
I was resetting them in the 4.2 (the one that still has an MBE) every time I made a change to the throttle linkage when I first got it going but it made the car drive terribly each time. Once they build up a corrected map for your engine (as long as everything is working correctly) they really help to make it drive better. The 4.2 just gets smoother every time I drive it now.
If your temp sensor mishap was recently it could well be worth resetting your adaptives, so they can build up a new map, do make sure the throttles are as balanced as you can first though - that is much more of a pain on the 4.5 though!
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